Executives and lawyers working for Comcast Corp. and its programming arm NBCUniversal Media LLC may be toiling hard on New Year's Eve as a spate of carriage agreements face expiration.

NBCU said it reached an impasse in its negotiations to strike a deal by year-end with Charter Communications Inc. As a result, NBC owned-and-operated stations, plus a bevy of entertainment and sports networks under its cable portfolio, may go dark on Charter, which has morphed into the nation's third-largest distributor through its acquisitions of Time Warner Cable Inc. and Bright House Networks LLC.

The prospects of forging new pacts between NBCU and Charter seemed tenuous at press time, as the programmer said the two sides are no longer negotiating.

"NBCUniversal values its partnership with Charter Spectrum, our third largest distributor," the programmer said in a statement. "Charter Spectrum has been unyielding in its demand for terms superior to those agreed to by the rest of the industry, including larger distributors. Given this position, we feel the responsibility to inform viewers that Charter Spectrum may drop NBCUniversal's networks at the end of the year."

In the event of a blackout, Charter subscribers could miss the final "Sunday Night Football" game of the year between the Green Bay Packers and Detroit Lions, a contest rife with NFL playoff implications, as well as the NHL Centennial Classic and Premier League soccer on NBC, plus the Golden Globe Awards on Jan. 8.

Charter declined comment, but noted it would be NBCU's decision to pull the various signals.

Comcast's cable arm, meanwhile, faces contract expiration Dec. 31 with 21st Century Fox Inc. for FOX News Channel, the top-ranked cable channel in 2016 in both prime time and total-day, as well as for a dozen regional sports networks.

Comcast's contracts will also expire with over 200 stations, cutting across affiliations with CBS, NBC, FOX, ABC, The CW and independents, as well as Univision and UniMás stations. The contract for Univision Communications Inc.'s cable network, Galavision, is also about to expire.

"Our agreements with content providers expire from time to time," Comcast said in a statement. "We are actively negotiating with a small number of them to continue carrying their programming after December 31. So long as they continue to reciprocate our good faith negotiations, we believe we will be able to reach agreements."

FOX and Univision officials declined to comment.

A Comcast spokesman said a contract extension had been reached with Time Warner Inc.'s HBO/Cinemax. That agreement, which continues carriage of the two premium services into March, supersedes the deal that was set to expire Dec. 31.

Elsewhere as part of the year-end scramble, top-ranked distributor AT&T Inc. and its DIRECTV unit are in the midst of retransmission-consent negotiations with stations owned by both Hearst Corp.'s Hearst Television Inc. and Cox Enterprises Inc.

Hearst Television has alerted DIRECTV subscribers in 26 markets that if the parties do not come to terms on a new retransmission-consent deal, viewers could lose access to the stations.

"Hearst has a long history of successfully concluding carriage agreements with cable companies and other satellite distributors with no disruption of service to subscribers," the broadcaster wrote in a statement on its local channels' web sites. "While we believe that we and DIRECTV can conclude our negotiations before January 1st, so as not to deprive any of our respective viewers and customers of our programming, we want to advise our viewers and customers that the possibility of non-renewal of our current agreement exists."

A Hearst spokesman said the sides were still negotiating at press time.

Cox's television stations also began notifying their viewers of a possible service disconnection involving AT&T U-Verse and DIRECTV as deals expire at 11:59 p.m. PT on Dec. 31. This disruption could affect AT&T U-Verse and DIRECTV subscribers in Atlanta; Boston; Charlotte, N.C.; Dayton, Ohio; Jacksonville, Fla.; Memphis; Orlando; Pittsburgh; Seattle; and Tulsa, Okla.

While Cox representatives did not respond by press time, AT&T said certain station owners are "threatening to block their signals ... unless they receive a significant increase in fees."

The telco added: "Some of these owners, like Cox Broadcasting, have threatened or blacked out other providers' customers before, so we appreciate our DIRECTV and U-verse customers' patience as we work to resolve this matter quickly and reasonably."

Meanwhile, Cable One Inc. is facing its own retrans squabbles with Hearst and Northwest Broadcasting in select markets.

Cable One said it is in negotiations for four stations in Grenada and Cleveland, Miss., owned by Northwest Broadcasting, which is seeking a nearly 100% rise in retrans rates, as well as Hearst stations serving 16 of the MSO's markets and which are said to be asking for upward of a 100% increase.

Officials at Cable One and Hearst said discussions are ongoing. The cable operator said it is still talking with Northwest, which did not respond by press time.

In terms of a peaceful resolution ahead of the new year, one potential disruption was averted in the days before Christmas when Altice NV's Altice USA reached a renewal deal with AMC Networks Inc., ahead of the Dec. 31 contract expiration. Terms and length were not disclosed, although sources familiar with the pact said it was a long-term agreement.